The Optical and Electrical Properties of Low Density Polyethylene Films in CuSo4 Solution

Abstract

The optical and electrical properties of pure and treated low density polyethylene (LDpE) were investigated. These measurements have been carried out at various times of immersion for LDPE films in 10% solution of CuSO+. The optical absorption spectra were measured in the wavelength range 200—► ll00 nm. The optical energy gaps and energy bandwidth of the tall of localized state (Eoo1 and AE) were calculated at different times of exposure to CuSOa. The a.c. conductivity was studied in frequency range 102 —> I}s Hz. The data of a.c. conductivity were analyzed. to obtain the d.c. conductivity (o'6") and the optical dielectric constant (e'-). The results of this study show that: (1) Direct and indirect optical transitions exist, (2) Direct and indirect energy gaps increase as the exposure time increases, (3) The Urbach energy band tail decreases as time increases, (4) The d.c. conductivity decreases, while the dielectric constant increases as time increases. These results could be explained by the fact that sulfate ions have caused formation of voids and degradation of the LDPE as time increased.